| 摘要 |
PURPOSE: To avoid the generation of a large accident such as a breakage of a Hume pipe and the like, by grasping the converting point from a propelling method to a shield processing method securely. CONSTITUTION: A shield excavator 20 can excavate under the ground in a normal shield construction method by propelling a shield main body by taking a reaction to a segment 26 by a shield jack 28. And the shield excavator 20 is propelled by a basis pressing jack 12 at the former half of the processing section, and it excavates a tunnel by a propelling method. When a controller 30 operates a pressure switch 18 provided to a duct 56 to feed the pressure oil to the basis pressing jack 12, the driving motor 68 of a jack pump 14 to feed the pressure oil to the basis pressing jack 12 is stopped, as well as the driving of a cutter driving motor 36 to rotate the cutter head 24 of the shield excavator 20 is stopped, so as to stop the propelling construction method, and the stopping condition is displayed on a display device. |
